Пример вызова:
static void Main(string[] args)
{
Console.WriteLine("1D, 10 width");
var noice = SimplexNoise.Calc1D(10, 0.3f);
foreach (float n1 in noice)
{
Console.WriteLine(n1);
}
} Класс Simplex шума:
public static class SimplexNoise
{
public static float[] Calc1D(int width, float scale)
{
var values = new float[width];
for (var i = 0; i < width; i++)
values[i] = Generate(i * scale) * 128 + 128;
return values;
}
public static float[,] Calc2D(int width, int height, float scale)
{
var values = new float[width, height];
for (var i = 0; i < width; i++)
for (var j = 0; j < height; j++)
values[i, j] = Generate(i * scale, j * scale) * 128 + 128;
return values;
}
public static float[,,] Calc3D(int width, int height, int length, float scale)
{
var values = new float[width, height, length];
for (var i = 0; i < width; i++)
for (var j = 0; j < height; j++)
for (var k = 0; k < length; k++)
values[i, j, k] = Generate(i * scale, j * scale, k * scale) * 128 + 128;
return values;
}
public static float CalcPixel1D(int x, float scale)
{
return Generate(x * scale) * 128 + 128;
}
public static float CalcPixel2D(int x, int y, float scale)
{
return Generate(x * scale, y * scale) * 128 + 128;
}
public static float CalcPixel3D(int x, int y, int z, float scale)
{
return Generate(x * scale, y * scale, z * scale) * 128 + 128;
}
static SimplexNoise()
{
_perm = new byte[PermOriginal.Length];
PermOriginal.CopyTo(_perm, 0);
}
public static int Seed
{
get => _seed;
set
{
if (value == 0)
{
_perm = new byte[PermOriginal.Length];
PermOriginal.CopyTo(_perm, 0);
}
else
{
_perm = new byte[512];
var random = new Random(value);
random.NextBytes(_perm);
}
_seed = value;
}
}
private static int _seed;
private static float Generate(float x)
{
var i0 = FastFloor(x);
var i1 = i0 + 1;
var x0 = x - i0;
var x1 = x0 - 1.0f;
var t0 = 1.0f - x0 * x0;
t0 *= t0;
var n0 = t0 * t0 * Grad(_perm[i0 & 0xff], x0);
var t1 = 1.0f - x1 * x1;
t1 *= t1;
var n1 = t1 * t1 * Grad(_perm[i1 & 0xff], x1);
return 0.395f * (n0 + n1);
}
private static float Generate(float x, float y)
{
const float F2 = 0.366025403f;
const float G2 = 0.211324865f;
float n0, n1, n2;
var s = (x + y) * F2;
var xs = x + s;
var ys = y + s;
var i = FastFloor(xs);
var j = FastFloor(ys);
var t = (i + j) * G2;
var X0 = i - t;
var Y0 = j - t;
var x0 = x - X0;
var y0 = y - Y0;
int i1, j1;
if (x0 > y0) { i1 = 1; j1 = 0; }
else { i1 = 0; j1 = 1; }
var x1 = x0 - i1 + G2;
var y1 = y0 - j1 + G2;
var x2 = x0 - 1.0f + 2.0f * G2;
var y2 = y0 - 1.0f + 2.0f * G2;
var ii = Mod(i, 256);
var jj = Mod(j, 256);
var t0 = 0.5f - x0 * x0 - y0 * y0;
if (t0 < 0.0f) n0 = 0.0f;
else
{
t0 *= t0;
n0 = t0 * t0 * Grad(_perm[ii + _perm[jj]], x0, y0);
}
var t1 = 0.5f - x1 * x1 - y1 * y1;
if (t1 < 0.0f) n1 = 0.0f;
else
{
t1 *= t1;
n1 = t1 * t1 * Grad(_perm[ii + i1 + _perm[jj + j1]], x1, y1);
}
var t2 = 0.5f - x2 * x2 - y2 * y2;
if (t2 < 0.0f) n2 = 0.0f;
else
{
t2 *= t2;
n2 = t2 * t2 * Grad(_perm[ii + 1 + _perm[jj + 1]], x2, y2);
}
return 40.0f * (n0 + n1 + n2);
}
private static float Generate(float x, float y, float z)
{
const float F3 = 0.333333333f;
const float G3 = 0.166666667f;
float n0, n1, n2, n3;
var s = (x + y + z) * F3;
var xs = x + s;
var ys = y + s;
var zs = z + s;
var i = FastFloor(xs);
var j = FastFloor(ys);
var k = FastFloor(zs);
var t = (i + j + k) * G3;
var X0 = i - t;
var Y0 = j - t;
var Z0 = k - t;
var x0 = x - X0;
var y0 = y - Y0;
var z0 = z - Z0;
int i1, j1, k1;
int i2, j2, k2;
if (x0 >= y0)
{
if (y0 >= z0)
{ i1 = 1; j1 = 0; k1 = 0; i2 = 1; j2 = 1; k2 = 0; }
else if (x0 >= z0) { i1 = 1; j1 = 0; k1 = 0; i2 = 1; j2 = 0; k2 = 1; }
else { i1 = 0; j1 = 0; k1 = 1; i2 = 1; j2 = 0; k2 = 1; }
}
else
{
if (y0 < z0) { i1 = 0; j1 = 0; k1 = 1; i2 = 0; j2 = 1; k2 = 1; }
else if (x0 < z0) { i1 = 0; j1 = 1; k1 = 0; i2 = 0; j2 = 1; k2 = 1; }
else { i1 = 0; j1 = 1; k1 = 0; i2 = 1; j2 = 1; k2 = 0; }
}
var x1 = x0 - i1 + G3;
var y1 = y0 - j1 + G3;
var z1 = z0 - k1 + G3;
var x2 = x0 - i2 + 2.0f * G3;
var y2 = y0 - j2 + 2.0f * G3;
var z2 = z0 - k2 + 2.0f * G3;
var x3 = x0 - 1.0f + 3.0f * G3;
var y3 = y0 - 1.0f + 3.0f * G3;
var z3 = z0 - 1.0f + 3.0f * G3;
var ii = Mod(i, 256);
var jj = Mod(j, 256);
var kk = Mod(k, 256);
var t0 = 0.6f - x0 * x0 - y0 * y0 - z0 * z0;
if (t0 < 0.0f) n0 = 0.0f;
else
{
t0 *= t0;
n0 = t0 * t0 * Grad(_perm[ii + _perm[jj + _perm[kk]]], x0, y0, z0);
}
var t1 = 0.6f - x1 * x1 - y1 * y1 - z1 * z1;
if (t1 < 0.0f) n1 = 0.0f;
else
{
t1 *= t1;
n1 = t1 * t1 * Grad(_perm[ii + i1 + _perm[jj + j1 + _perm[kk + k1]]], x1, y1, z1);
}
var t2 = 0.6f - x2 * x2 - y2 * y2 - z2 * z2;
if (t2 < 0.0f) n2 = 0.0f;
else
{
t2 *= t2;
n2 = t2 * t2 * Grad(_perm[ii + i2 + _perm[jj + j2 + _perm[kk + k2]]], x2, y2, z2);
}
var t3 = 0.6f - x3 * x3 - y3 * y3 - z3 * z3;
if (t3 < 0.0f) n3 = 0.0f;
else
{
t3 *= t3;
n3 = t3 * t3 * Grad(_perm[ii + 1 + _perm[jj + 1 + _perm[kk + 1]]], x3, y3, z3);
}
return 32.0f * (n0 + n1 + n2 + n3);
}
private static byte[] _perm;
private static readonly byte[] PermOriginal = {
151,160,137,91,90,15,
131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23,
190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33,
88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166,
77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,
102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196,
135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123,
5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42,
223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9,
129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228,
251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107,
49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254,
138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180,
151,160,137,91,90,15,
131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23,
190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33,
88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166,
77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,
102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196,
135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123,
5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42,
223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9,
129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228,
251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107,
49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254,
138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180
};
private static int FastFloor(float x)
{
return (x > 0) ? ((int)x) : (((int)x) - 1);
}
private static int Mod(int x, int m)
{
var a = x % m;
return a < 0 ? a + m : a;
}
private static float Grad(int hash, float x)
{
var h = hash & 15;
var grad = 1.0f + (h & 7); // Gradient value 1.0, 2.0, ..., 8.0
if ((h & 8) != 0) grad = -grad; // Set a random sign for the gradient
return (grad * x); // Multiply the gradient with the distance
}
private static float Grad(int hash, float x, float y)
{
var h = hash & 7; // Convert low 3 bits of hash code
var u = h < 4 ? x : y; // into 8 simple gradient directions,
var v = h < 4 ? y : x; // and compute the dot product with (x,y).
return ((h & 1) != 0 ? -u : u) + ((h & 2) != 0 ? -2.0f * v : 2.0f * v);
}
private static float Grad(int hash, float x, float y, float z)
{
var h = hash & 15; // Convert low 4 bits of hash code into 12 simple
var u = h < 8 ? x : y; // gradient directions, and compute dot product.
var v = h < 4 ? y : h == 12 || h == 14 ? x : z; // Fix repeats at h = 12 to 15
return ((h & 1) != 0 ? -u : u) + ((h & 2) != 0 ? -v : v);
}
private static float Grad(int hash, float x, float y, float z, float t)
{
var h = hash & 31; // Convert low 5 bits of hash code into 32 simple
var u = h < 24 ? x : y; // gradient directions, and compute dot product.
var v = h < 16 ? y : z;
var w = h < 8 ? z : t;
return ((h & 1) != 0 ? -u : u) + ((h & 2) != 0 ? -v : v) + ((h & 4) != 0 ? -w : w);
}
}